Number of biopsies in diagnosing pulmonary nodules.

PURPOSE: To determine the number of specimens to be obtained from pulmonary lesions to get the highest possible accuracy in histological work-up. MATERIALS AND METHODS: A retrospective evaluation (January 1999 to April 2004) covered 260 patients with thoracic lesions who underwent computer tomography (CT)-guided core-cut biopsy in coaxial technique. All biopsies were performed utilizing a 19 gauge introducer needle and a 20 gauge core-cut biopsy needle. In all, 669 usable biopsies were taken (from 1-5 biopsies in each setting). The specimens were marked sequentially and each biopsy was worked up histologicaly. The biopsy results were correlated to histology after surgery, clinical follow-up or autopsy. The number of biopsies was determined that is necessary to achieve the highest possible accuracy in diagnosing pulmonary lesions. RESULTS: In 591 of 669 biopsies (88.3%), there were correct positive results. The overall accuracy was 87.4%. In 193 of 260 (74.2%) patients, a suspected malignancy was confirmed. In 50 of 260 (19.2%) patients, a benign lesion was correctly diagnosed. Seventeen (6.5%) patients were lost to follow-up. The first, second and third biopsies had cumulative accuracies of 63.6%, 89.2% and 91.5%, respectively (P < 0.02). More biopsies did not show any higher impact on accuracy. CONCLUSION: For the highest possible accuracy in diagnosing pulmonary lesions by CT-guided core-cut biopsy, at least three usable specimens are recommended to be taken.

Management of pancreatic trauma and its consequences--guidelines or individual therapy?

BACKGROUND/AIMS: Diagnosis of pancreatic trauma and its complications may be difficult due to non-specific signs and symptoms and treatment recommendations are not unequivocal. METHODOLOGY: Clinical data of a series of 47 patients with pancreatic trauma were analyzed; most of them were polytraumatized and treated by an interdisciplinary team. RESULTS: The most common causes were traffic accidents and sport injuries with 66% and 15%, respectively. Concomitant injuries were seen in 96% (nonpancreatic intra-abdominal injuries 85% including spleen 38% and liver 34%, extra-abdominal injuries 70%). Concomitant liver injuries were treated conservatively in 31% and operatively in 69% (including hepatic packing in 38%). Concomitant splenic injuries were usually very severe and could be managed conservatively in only 11%. All patients with pancreatic injuries grade III, IV or V (17%) according to the American Association of Surgical Trauma Classification required surgery, endoscopic treatment or interventional radiology. The most common posttraumatic complications were necrotizing pancreatitis (15%), pseudocyst formation (9%), abscesses (6%) and fistulas (4%). CONCLUSIONS: The status of the pancreatic duct is the crucial point for management of pancreatic trauma and should be assessed as early as possible. Treatment has to be tailored to the individual situation, especially in patients with severe concomitant injuries or prolonged course.

Surgical conversion of abdominal aortic stent-grafts--outcome and technical considerations.

OBJECTIVE: The purpose of this study was to evaluate the outcome of patients with stented abdominal aortic aneurysms who had to undergo open aneurysm repair with partial or total stent-graft removal. METHODS: Between October 1996 and December 2003, 117 patients with abdominal aortic aneurysms underwent endovascular repair. When open surgery was necessary during the initial and same anaesthesia as stent-graft implantation, it was defined as immediate conversion. When conversion was performed during a second anaesthesia, we defined it as late (acute or elective) conversion. RESULTS: A total of 33 patients underwent conversion to open surgery. In 7 (6%) patients, immediate conversion was necessary due to stent-graft misplacement and obstruction of the renal arteries (n=4), type Ia endoleaks (n=2) and stent-graft dislocation into the aneurysm sac (n=1). During a mean follow-up period of 39.6 months (min 0.03 months, max 80.4 months), 26 (23.6%) of the remaining 110 patients underwent late conversion to open surgery for endoleak (n=12), rupture (n=6), thrombosis (n=4), graft fatigue (n=2), aorto-duodenal fistula (n=1), and recurring peripheral embolisms (n=1). The mortality of acute conversion was 38% (5 of 13). Elective conversion did not lead to any mortality. CONCLUSION: Acute conversion of stented abdominal aortic aneurysms is associated with a high mortality. Elective stent-graft explantation with open aortic reconstruction is a safe but complex procedure.

Review of source images is necessary for the evaluation of gadolinium-enhanced MR angiography for renal artery stenosis.

The purpose of this study was to assess interobserver variability and accuracy in the evaluation of renal artery stenosis (RAS) with gadolinium-enhanced MR angiography (MRA) and digital subtraction angiography (DSA) in patients with hypertension. The authors found that source images are more accurate than maximum intensity projection (MIP) for depicting renal artery stenosis. Two independent radiologists reviewed MRA and DSA from 38 patients with hypertension. Studies were post-processed to display images in MIP and source images. DSA was the standard for comparison in each patient. For each main renal artery, percentage stenosis was estimated for any stenosis detected by the two radiologists. To calculate sensitivity, specificity and accuracy, MRA studies and stenoses were categorized as normal, mild (1-39%), moderate (40-69%) or severe (> or =70%), or occluded. DSA stenosis estimates of 70% or greater were considered hemodynamically significant. Analysis of variance demonstrated that MIP estimates of stenosis were greater than source image estimates for both readers. Differences in estimates for MIP versus DSA reached significance in one reader. The interobserver variance for MIP, source images and DSA was excellent (0.80< kappa< or = 0.90). The specificity of source images was high (97%) but less for MIP (87%); average accuracy was 92% for MIP and 98% for source images. In this study, source images are significantly more accurate than MIP images in one reader with a similar trend was observed in the second reader. The interobserver variability was excellent. When renal artery stenosis is a consideration, high accuracy can only be obtained when source images are examined.

Femoral artery infection associated with a percutaneous arterial suture device.

This is a case report of a femoral artery infection with fatal outcome after using a percutaneous suture mediated closure device: A 77-year old patient underwent diagnostic angiography of his thoracic and abdominal aortic aneurysm, the puncture site was closed with the Perclose system. He developed a staphylococcal femoral artery infection with groin abscess, requiring surgical intervention with debridement and removal of the Perclose suture. After stent graft exclusion of the thoracic and abdominal aortic aneurysm a staphylococcal sepsis occurred and the patient died of aneurysm rupture months later despite long term antibiotic therapy. Since the use of the Perclose device carries an increased risk of femoral artery infection with septic endarteritis and bacteremia, it should not be used in routine diagnostic angiography.

Serum osteoprotegerin is a major determinant of bone density development and prevalent vertebral fracture status following cardiac transplantation.

Osteoprotegerin (OPG) is an antiresorptive cytokine and a key regulator of osteoclastogenesis and activity. Since OPG is downregulated by glucocorticoids and cyclosporine A in vitro we examined whether immunosuppressive therapy would play a role in the development of transplantation osteoporosis. We enrolled 57 cardiac transplant recipients (median time since transplantation, 3.2 years (1.1-11.5 years)) in this cross-sectional study. Standardized spinal X-rays as well as hip bone density measurements were performed in all patients. Serum OPG was determined using a commercially available ELISA. Vertebral fractures were present in 56% of the patients. Bone densities of all femoral neck subregions were correlated to serum OPG concentrations (r values between 0.40 and 0.48, all P < 0.005). Multiple regression analysis revealed OPG levels to be independently correlated to femoral neck Z scores (r = 0.49, P = 0.002). After adjustment for age, BMI, neck Z score, renal function, and months since transplantation, serum OPG was the only significant predictor of prevalent vertebral fractures (P = 0.001). In a separate 6-month prospective study of 14 heart transplant recipients receiving calcium and vitamin D serum OPG levels fell by 41% (P = 0.0004) after 3 months and 47% (P = 0.0001) after 6 months following cardiac transplantation. Bone loss at the lumbar spine and femoral neck after 6 months was correlated to the decrease in serum OPG at 6 months (r = 0.82, P < 0.0001, and r = 0.60, P = 0.02, respectively) as well as 3 months after cardiac transplantation (r = 0.65, P = 0.01, and r = 0.69, P = 0.006, respectively). Serum OPG alone accounted for 67% of the variance of lumbar spine bone density changes over the first 6 months posttransplantation. We conclude that serum OPG levels decline consistently in all patients following initiation of immunosuppressive therapy and are independently correlated with changes in bone density. We hypothesize that OPG plays a major role in the development of transplantation osteoporosis.

[The value of different spiral CT phases in the detection of liver metastases]. / Der Wert unterschiedlicher Spiral-CT-Phasen in der Suche nach Lebermetastasen.

PURPOSE: To assess the value of the non-contrast phase (NCP), hepatic-arterial phase (HAP) and portal-venous phases (PVP) for the detection of liver metastases by spiral CT. METHODS: In order to detect liver metastases, 119 patients (58 women, 61 men; mean age: 62 years) underwent triphasic spiral CT (8 mm collimation, 12 mm table increment/rotation, 7 mm reconstruction increment). NCP, HAP (20 s delay) and PVP (70 s delay) scans were acquired (contrast medium injection rate: 4 ml/s). CT analysis comprised independent evaluation of the three scan series for detection and conspicuity of liver metastases (conspicuity score: 0 = not visible, 1 = barely visible, 2 = clearly visible, 3 = distinctly visible). RESULTS: In 83 of the 119 patients, 478 liver metastases were detected (110 hypervascular and 368 hypovascular lesions). 285 (60 %) metastases were detected on NCP scans. Significantly more lesions were seen on HAP (n = 375, 78 %) and on PVP (n = 428, 90 %). No lesion was detected on NCP studies alone. For all detected metastases, mean conspicuity was 1.2 +/- 0.4 on NCP, 1.8 +/- 0.8 on HAP and 2.2 +/- 0.8 PVP. Hypervascular lesions were best seen on HAP with a conspicuity score of 2.0 +/- 0.8 versus 1.3 +/- 0.5 on NCP and 1.5 +/- 0.8 on PVP. Hypovascular lesions reached the highest conspicuity on PVP with 2.4 +/- 0.8 versus 1.2 +/- 0.4 on NCP and 1.7 +/- 0.7 on HAP. CONCLUSION: For detection of liver metastases with spiral CT, contrast series seem to be sufficient. For tumors likely to seed hypervascular metastases, HAP scans should be applied in addition to the PVP.

Placement of Hemobahn stent-grafts in femoropopliteal arteries: early experience and midterm results in 18 patients.

PURPOSE: To determine the outcome of a new polytetrafluoroethylene (PTFE)-covered stent-graft in the treatment of occlusive lesions of the femoropopliteal arteries. MATERIALS AND METHODS: Eighteen patients with intermittent claudication (Fontaine stages IIb-IV; Rutherford classes I/2-III/5) and occlusive lesions of the superficial femoral and/or popliteal artery were treated with use of a new PTFE-covered stent-graft (Hemobahn). Indication for stent-graft insertion was an unsatisfactory result after balloon dilation. RESULTS: Successful stent-graft placement was achieved in 17 patients (94%). In one patient, additional insertion of a Palmaz stent was necessary because of a stent-graft wrinkle. Mean ankle-brachial index increased from 0.72 +/- 0.15 preoperatively to 0.94 +/- 0.17 postoperatively (P =.028). Fifteen patients (83%) experienced an initial improvement of at least one clinical stage. Primary patency was 61% +/- 11% at 3 months and 49% +/- 12% at 6 months. Stent-graft occlusion was observed in 13 patients (72%). In four patients, the stent-graft was reopened percutaneously by balloon angioplasty (n = 2) and/or rotational thrombectomy (n = 2). Therefore, the secondary patency rate was 67% +/- 11% at 3 months and 61% +/- 11% at 6 months. Patency rates proved to be significantly lower for stent-grafts longer than 10 cm (P =.03). Intimal hyperplasia at the proximal or distal end of the stent-graft was observed in seven patients (39%). Complications such as access site hematoma (n = 3), distal thromboembolism (n = 2), and abscess formation around the stent-graft (n = 1) were observed. CONCLUSION: Despite excellent initial angiographic results, the patency rate in lesions treated with the Hemobahn stent-graft in this small study was unsatisfactory. Use of stent-grafts longer than 10 cm and the occurrence of intimal hyperplasia proved to be major factors in the reduction of long-term patency rates.

CT number variations due to different image acquisition and reconstruction parameters: a thorax phantom study.

A humanoid thorax phantom containing six compartments was scanned with two different computed tomography (CT) scanners using various image acquisition and reconstruction parameters. The differences of CT numbers were statistically significant between the two CT scanners for each compartment (p<0.001) except for the "air" compartment. The variabilities of the CT numbers are described for the different parameters. The mean CT numbers of the "water" compartment, for instance, ranged from 1 to 15HU (Hounsfield Units), those of the "air" compartment varied from -962 to -990HU. Knowledge of these CT number variabilities is necessary when CT numbers are used for tissue characterization.

[Acute appendicitis in non-contrast spiral CT: a diagnostic luxury or benefit?]. / Akute Appendizitis im Nicht-Kontrast-Spiral-CT: diagnostischer Luxus oder Nutzen?

PURPOSE: To evaluate the diagnostic accuracy of thin collimated unenhanced spiral-CT in patients with clinically suspected acute appendicitis and to determine the impact on patient management and overall costs. METHOD: Unenhanced focussed appendiceal spiral-CT was performed in 56 patients (23 women and 33 men) with clinically suspected acute appendicitis. Scans were obtained from the L4 level to the symphysis pubis using 5 mm collimation, 7.5 mm table feed (pitch 1.5) and 4 mm increment without i.v., oral, or rectal contrast material. Prospective diagnoses based on CT findings were compared with surgical (and histopathological) results and clinical follow-up. The effect of spiral-CT on patient management and clinical resources was assessed. RESULTS: 29 patients (10 women and 19 men) underwent appendectomy. Unenhanced spiral-CT was an accurate imaging technique for the initial examination of patients with suspected acute appendicitis with a sensitivity of 95.4% and a specificity 100%, an accuracy of 98.2%, a positive predictive value of 100%, and a negative predictive value of 97.1%. In 27 patients with no evidence of acute appendicitis, an alternative diagnosis could be made in 24 patients by unenhanced spiral-CT. CONCLUSION: Unenhanced spiral-CT is an accurate test to diagnose or to exclude acute appendicitis. Routine appendiceal spiral-CT can improve medical care and reduce the overall costs for patients suspected of having acute appendicitis.